For Gabriel Jesus, it was the ultimate show of faith from Pep Guardiola.
In a season when Jesus has struggled to convince, picking him ahead of Sergio Aguero for the biggest game of Manchester City's season was a huge call from Guardiola.
But Guardiola is fond of making such bold decisions in big games and clearly felt Jesus had earned the right to start with his goal-scoring cameo in last weekend's 1-0 win at Leicester.
Deployed on the left, effectively as a wing-back, to assist Benjamin Mendy, Jesus was forced to curb his own natural attacking instincts here and show a different facet to his game.
The 22-year-old displayed discipline and diligence in his unfamiliar role, sticking to the instructions laid down by Guardiola and carrying out the game-plan to nullify Real down City's left and keep it tight.
Despite the defensive duties he was ordered to undertake, the best chance of the first-half fell to Jesus, who took delivery of a Kevin De Bruyne pass before cutting inside onto his right foot.
Having got the better of Carvajal, beating Thibaut Courtois was a step too far for Jesus, whose curling effort was palmed away by the Real goalkeeper.
There was a second chance for Jesus just before the break, when his low angled drive was blocked by Sergio Ramos, who almost sliced it into his own net, before it was cleared by Casemiro.
The remit from Guardiola was clearly to not afford Real the space and freedom to hurt City, with Jesus playing a pivotal role in the fulfilling of that objective, until the 60th minute.
City were on top, with Jesus having moved back into his favoured central role, when calamitous defending allowed Isco to score and Real to seize the initiative at the halfway stage of the tie.
And it was here the Brazilian truly thrived.
The Brazil striker made it third time lucky in the 78th minute, rising above Real skipper Sergio Ramos to head City level and give the Blues a precious away goal.
Only eight minutes later, now with City winning thanks to Kevin de Bruyne's penalty, Jesus was giving Ramos problems again, cutting across and going clean through. Ramos sent him tumbling to the turf and was promptly sent off, the Madrid captain now out of the second leg.
On a night full of industry and application, Jesus got his rewards and justified Guardiola's decision to pick him ahead of Aguero on a historic night for City.
